Search

Premium Membership ♕

CYBER WEEK OFFER đź’Ą Save 20% on PRO Membership Plan and Video Courses with the coupon CYM23 and learn from experienced engineers.

Home / Technical Articles / Mastering single line and wiring diagrams: Using circuit breaker for MV power factor correction

MV reactive power compensation

Within this article, a custom-made cubicle intended for supply and protection of MV reactive power compensation block will be analyzed. Technical characteristics of major electrical components, together with three line and wiring diagrams, will be shown, while some specific aspects of this type of application will be underlined.

Mastering single line and wiring diagrams: Using circuit breaker for MV power factor correction
Mastering single line and wiring diagrams: Using circuit breaker for MV power factor correction

Technical description and wiring diagrams of MV cubicle

The reactive power compensation block, which is the subject of this article, is consisting of a three-phase reactor connected in series with a “double star” configuration capacitor battery made of single-phase capacitors.

Main characteristics of this compensation block are as follows:

Capacitors:Double star connection of 6 single phase capacitors, each capacitor with rated voltage of 13.8 kV, and rated power of 220 kvar
Reactor:Three phase, iron core, filtering factor 7%, rated voltage 24kV
Rated power of compensation block:1000kvar @ 20kV
Mounting type:Freestanding, inside the cabinet, on steel made support

This compensation block is designed for PFC purposes of 20kV rated switchgear inside substation for supply of large coal mining excavators. It is mounted inside a custom-made cabinet, together with electrical equipment for supply and protection.

The cabinet is made of metal-enclosed frame, air-insulated type, for outdoor installation, with approximate dimensions (HxWxD) 2000x2800x1200 mm. If you take a closer look at the specification of reactor and capacitors, you may easily see that the rated voltage of single-phase capacitors (13,8kV) corresponds to the phase-to-phase rated voltage of 24kV, which is the typical standardized value of rated voltage for equipment designed for the use inside 20kV rated installation. The same applies to a three-phase reactor.

You may also note that compensation block is intended for so-called “detuned” power factor correction, which was analyzed in detail within one of the previous articles. This is caused by higher harmonic distortion expected in the point of compensation block installation.

Remember that, in the case of reactor and capacitor connected in series, capacitor’s voltage will be higher than incoming reactor’s voltage, i.e. higher than the supply voltage of the block as a whole.

So, having above said in mind, are we able to say that the whole block (capacitors plus reactor) is 24kV rated?

Premium Membership Required

This technical article/guide requires a Premium Membership. You can choose an annually based Plus, Pro, or Enterprise membership plan. Subscribe and enjoy studying specialized technical articles, online video courses, electrical engineering guides, and papers. With EEP’s premium membership, you get additional essence that enhances your knowledge and experience in low- medium- and high-voltage engineering fields.

Check out each plan’s benefits and choose the membership plan that works best for you or your organization.

CYBER WEEK DEAL đź’Ą – Save 20% on PRO plan with the coupon CYM23.

Log In »Purchase »

Premium Membership

Get access to premium HV/MV/LV technical articles, electrical engineering guides, research studies and much more! It helps you to shape up your technical skills in your everyday life as an electrical engineer.
More Information
author-pic

Miodrag Kokotovic

Graduated from Faculty of Electrical Engineering, within University of Belgrade, in the field of electrical power systems. Expert in electrical part of tender preparation, design, procurement, construction and commissioning of treatment plants and pumping stations, electrical power quality and energy management.

Leave a Comment

Tell us what you're thinking. We care about your opinion! Please keep in mind that comments are moderated and rel="nofollow" is in use. So, please do not use a spammy keyword or a domain as your name, or it will be deleted. Let's have a professional and meaningful conversation instead. Thanks for dropping by!

five  +  four  =  

Learn How to Design Power Systems

Learn to design LV/MV/HV power systems through professional video courses. Lifetime access. Enjoy learning!

Subscribe to Weekly Newsletter

Subscribe to our Weekly Digest newsletter and receive free updates on new technical articles, video courses and guides (PDF).
EEP Academy Courses - A hand crafted cutting-edge electrical engineering knowledge